Archaeologists with the Australian National University have discovered fossils of seven different species of giant rats, one of which could grow to be up to 10 times the size of the ones that scurry through New York City’s subways.

The archaeologists found the fossils in East Timor while working on a project examining early human movement in Southeast Asia. These fossils are around 44,000 years old. Evidence suggest that humans, who lived in Timor as much as 46,000 years ago, would hunt and eat the mega-rats.

One of the most interesting aspects of the rats is how scientists suspect they died out, and the implications that could have for life today. The reason researchers think they became extinct about 1,000 years ago is because that was when metal tools began to be introduced in Timor, people could start to clear forests on a larger scale.

It wasn’t the presence of human hunters using traditional weapons that caused the extinctions of the giant rats. It was actually deforestation and destruction of the habitat. When you consider there are similar things happening now in areas around Papua New Guinea and Indonesia, it’s really important to keep in mind the effects of deforestation could cause many more extinctions.